Thermo-electric relay.



T. E. CLARK.

THERMO ugcpmc RELAY.

APPLICATION FILED MAR. 1, I912- Patented Oct. 24, 1916.

2 shins-SHEET T. E. CLARK. THERMO ELECTRIC RELAY.

APPLICATlON FILED MAR. 1. I912.

Patented OCT. 2-1, 1916.

2 SHEETS-SHEET 2 ihmrulur PATENT omen.

THOMAS E. CLARK, 0F DETROIT, MICHIGAN.

THERMO-ELECTRIC RELAY.

To all 2072-0122 it may concern Be it known that I, THOMAS E. CLARK, a.citizen of the United States, residing at Detroit, in the county ofVayne, State of Michigan, have invented certain new and usefulImprovements in Thermo-Electric Relays; and I do declare the followingto be a full, clear, and exact description of the invention, such aswill enable Others skilled in the art to which it appertains to make anduse the same, reference being had to the accompanying drawings, and tothe characters of reference marked thereon, which form a part of thisspecification.

This invention relates to a thermo-electric relay or responder, adaptedto be actuated by the flow of an impressed current in a receivingcircuit, to close a local circuit to effect the energization of a relayplaced therein, or to directly or indirectly actuate electrical ormechanical instrumentalities for the performance of predeterminedfunctions.

The invention consists in the construction. association and cooperationof parts hereinafter more fully set forth and pointed out particularlyin the claims. s

The object of the invention is to provide a simple and efficientinstrument which shall respond to the flow of current in a receivingcircuit impressed therein from a circuit radiating high-frequencyhigh-potential current energy. The purpose of said instrument. which ispreferably in the form of a thermo-electric relay, is to utilize thecurrent energy flowing in the receiving circuit to close a local circuitor cause the actuation of electrical or mechanical devices for thecontrol of railway signals or for other purposes. I

The above object is obtained by the apparatus and associated circuitsillustrated in the accompanying drawings in which Figure 1 is a planview of the thermoelectric relay showing in detail the construc I tionthereof and also illustrating a local circuit connected therewith andthe receiving circuitin which said relay is included. Fig. 2 is atransverse section through said thermoelectric relay as on line 2-2 ofFig. 1. Fig. 3 is. a diagrammatical view showing my thermo-electricrelay in a receiving circuit adapted to have impressed therein a currentflow from a radlatmg circuit, which latter circuit is connectedadjustably with a circuit in which high-frequency high-potential 0s-Specification of Letters Patent.

Patented Oct. 24, 1916.

Application filed March 1 1912. Serial No. 680,970.

cillating currents are generated. Said view also illustrates a localcircuit connected with the thermo-electric relay to be opened and closedby the operation thereof. Fig. at. is a similar view with the generatingand radiating circuits omitted. showing the thermoelectric relay ashaving responded to. the flow of current in the receiving circuit andclosed said local circuit. Fig. 5 is a perspective view of the rotatablecommutator of the thermo-electric relay. through the operation ofwhichthe local circuit is opened and closed. Fig. 6 is a sectional view ofsaid commutator transversely of its shaft.

Referring to the drawings and the characters of reference thereon. 1designates a suitable base of insulating material. Mounted upon saidbase. is a suitable case 2 also of insulating material. in which theparts comprising the thermo-electric relay are located. Rigidly securedto the back of the case 2 is a metal bracket 3. having laterallyextending and slightly flexible portions 4. provided with laterallyextending curved arms 5. Connecting the curved arms of the extensions 4of the bracket is a strong curved spring 6. Engaging the upper arc ofsaid spring is adjusting screw 7. which is threaded'in a suitablesupport 8. Mounted in the ends of the lateral extensions -.t of saidbracket at the point'of juncture of the curr'ed arms therewith. are theposts 9. which are insulated from the bracket bv the insulating blocks10. Extending be-- tween and electrically connecting the posts 9 is afine wire filament 11 of high resistance and low temperature coefficientand preferably of non-oxidizable metal. 7

The receiving circuit in which this thermoelectric relay is locatedcomprises a harp 12 consisting of a plurality of wires, the line 13,leading from said harp to a binding post 14 on said thermo-electricrelay. From said binding postthe receiving circuit continues on theconductor 15 to one of the conducting posts 9, thence on the fine wirefilament 11 to the other post 9, from which leads a conductor 16 to'abinding post 17. From said binding post-17 the remaining portion of thereceiving circuit comprises the line 18, the variable inductance 19,with which said line'is adjustably connected, and the ground 20. It willtherefore be understood that thefine wire filament 11 is included inandforms a part of said receiving circuit. The

functions of the harp 12 are the same as bracket 23, supported in thecase of the re- I lay. Fastened to the shaft 22 at one end and securedat the other end to a fixed pin 2%, on the bracket 23, is a coiledspring 25. The tension of said spring is normally exerted to rotate theshaft 22, and the tendency of said shaft to turn is resisted by the silkcord 21, which, through the tension of the spring, exerts a continualdownward stress upon the wire filament 11.

A proper tension is maintained on the wire 11 through the medium of thescrew 7. By manipulating said screw a downward pressure may be exertedupon the spring 6, which, being connected with the arms 10 of thelaterally extending portions l of the bracket 3, will cause a slightspreading of said arms and the placing of a longitudinal stress upon thefilament 11. It will therefore be seen that by a manipulation of saidscrew the tension on the filament 11 may be regulated in accordance withthe requirements under working conditions.

The thermo-electric relay as herein illustrated is employed for closinga local electric circuit, comprising a source of energy' 26, the line 27leading therefrom to binding post 28, the lines 29 leading from saidbinding post to the pillars'30, upon which the contact arms 31 aremounted, through said arms and the contact plates 32 set in the disk 33of insulating material carried on the shaft 22. and electricallyconnected with said shaft as shown in Fig. 5; the other side of saidlocal circuit being completed on line 3* which leads from the frame orbracket in which said shaft is mourfted to binding post 35, and thenceon line 36 through relay 37 to source of energy 26.

The local circuit just described is nor-- mally open at the insulatingdisk 33, the terminals of the contact arms 31 resting upon theperipheryof said insulating disk, out of contact with the plates 32, as shown inFig. 3, except when the thermo-electric relay is actuated in response tothe passage of a current over the receiving circuit.

\Vhen current is impressed upon the receiving circuit from a circuit 38adapted to radiate high-frequency high-potential currents, the passageof such current over the filament 11 of the thermo-electric relay willheat said filament and cause it to expand and sag, thereby allowing thespring 25 to rotate the shaft 22 sufiiciently to cause the contactplates 32 in the disk 33, to make electrical contact with the terminalsof the contact arms 31, effecting a closing of the local circuit throughthe relay 37, and energizing said rela'yeto actuate the armature 39thereof to engage the contact point 40, and close a second circuit 11having therein a source of energy 42 adapted to energize an element -13for the performance of any.

desired function, a situation illustrated in Fig. Upon a cessation ofcurrent in the receiving circuit, the fine wire filament 11 will cooland contract, thereby drawing upwardly upon the cord 21, and turning theshaft 22 such distance as to carry the contact plates 32 thereon out ofengage ment with the terminals ofthe contact arms 31, and open saidlocal circuit. It will be noted that the contact arms 31 are in shuntwith one another, an arrangement which provides for the closing of thelocal circuit by contact of either one of said arms with a contactplateon the rotatable disk 33.

This thermo-electric relay is designed for use in a receiving circuit inconnection with a generator of high-frequency high-potential oscillatingcurrents and a radiating circuit associated therewith adapted to impressupon said receiving circuit a current of highfrequency high-potentialenergy. In Fig. 3 I have diagrammatically illustrated one form of such agenerator and of such a radiating circuit. which I will now describe asfollows: An alternating current generator H is connected through circuitlines 45 and 46, including a reactance regulator 47 and a suitableswitch 48, with the primary-of a transformer 49. Connected across theterminals of the high-potential secondary of the transformer 49 is aspark gap 50. A high-potential oscillating circuit is formed to includesaid spark gap by means of the lines 51 and 52, in each of which isincluded a condenser 53. To complete said high-potential oscillatingcircuit, there is included therein one or more turns of an inductance orlinking coil 54, the line 51 of said high-potential oscillating circuitbeing acljustably connected to said linking coil in the usual manner inorder to vary the inductance in said circuit. circuit 38 is adjustablyconnected with the inductance 54 through the line 55. The closing of thespark gap in the highfrequency oscillating circuit is efl'ected throughthe medium of a disk 56 adapted to rotate at high velocity and havingthereon laterally projecting conducting studs 57, which, as the diskrevolves, pass between the electrodes 58 of the spark gap. The spark gapelectrodes are so adjusted as to form between them an air gap which isnormally too great for the oscillating current to spark across. As thedisk 56 revolves, the projecting studs thereon passing between theelectrodes shorten the air gap between them, thereby enabling thecurrent to spark across said gap, and causing high frequency high- Theradiating potential oscillating-current discharges to take place in theoscillating circuit. If the sparking disk be timed in its rotation withrespect to the capacity and inductance of the radiating circuit, saidcircuit will radiate the electrical energy supplied to it from thegenerating circuit, and will continue, while said condition obtains, toradiate electrical energy of a frequency and potential depending uponthe: adjustment or tuning of the highfrequency oscillating circuit. Whenhigh-frequency high-potential current is being generated as described,and radiated from the radiating circuit 38, and the harp or collector 12of the receiving circuit is disposed in proximity to said radiatingcircuit, a strong flow of high-potential current will be impressed uponsaid receiving circuit of a value varying. in accordance with the tuningthereof, and will actuate the responder or thermo-electric relay placedin said receiving circuit to close a local circuit as before described,or to perform such other functions as may properly. come withinthe'scope of an instrument of this character.

By heavily insulating the parts included in the receiving circuit orforming a path for the receiving circuit current, a highfrequencyhigh-potential current may be readily utilized to actuate the responderor thermo-electric relay as described.

This responder or thermo-electric relay is especially desirable for usein connection with signaling and train controlling devices, employed inblock signal systems of train control, where said devices are mounted ona locomotive or other movable vehicle, and where the thermo-electricrelay or responder which renders said devices operative or inoperativemust also be carried upon said locomotive or other vehicle, and subjectto the jar and vibration incident tor the his thermo-electric relay isnot affected by the jar or vibration of a locomotive or any othermovable vehicle upon which it may be mounted, and will respond to theflow of a current through the receiving circuit to close a'local circuitor perform any other function as effectively when the locomotive ismoving at a high rate of speed, as it would were the locomotive standingstill. The construction of the instrument is such that upon the breakingof the cord 21 or the breaking of the filament 11, the spring 25 willrevolve the shaft 22, so as to carry the contact plates 32 in theinsulating disk 33 to a. point out of contact with the arms 31 in thelocal circuit, thereby obviating the accidental closing of the localcircuit through injury or accident to the responder or thermo'- electricrelay Having thus fully set forth my invention,- what I claim as new anddesire to. secure by Letters Patent is 1. In a thermo-electric relay, afilament of high resistance forming a part of a receiving circuit, alocal circuit, a rotary disk of forming a path for an electric currentex- 4 tending between and connecting said posts, means for varying thetension on said filament, a rotatable disk of insulating material, acontact plate thereon forming a terminal of a. local circuit, a springcontact arm forming the other terminal'of said local circuit, normallyengaging the periphery of said disk, and means operatively associatedwith said parts and actuatable by a flow of current over said filamentto cause said disk to rotate and carry the contact plate thereon intoengagement with said contact arm and close said local, circuit, saidmeans being operative to turn said disk in the opposite directionand'open said local circuit, upon a cessation of the current flow oversaid filament. v

3. In a thermo-electric relay, the combination of a pair of supports,.afilament tensioned between them and adapted to receive current energy, alocal circuit contalnmg a spring contact, a rotary disk of insulatingmaterial having a .contact plate, means for H.. R. MILLER, J. O'r'roBAENZIGER.

